United States Armed Forces Abbreviations

Each U.S. Army Air Forces (USAAF) aircraft was assigned a unique designation that identified it’s intended purpose, model, series and special purpose. The coding system used during the period 1939 to 1945, (which is still in use today by all branches of the U.S. military), was introduced by the U.S. Army Air Service in May 1924; in 1941 additional characters were introduced to uniquely identify similar aircraft and/or aircraft produced by different manufacturers. The U.S. Air Force was established on 26 Sep 47 and in 1948, a number of prefixes and type symbols were changed notably "P" for pursuit was changed to "F" for fighter; other changes to World War II codes are defined in the following paragraphs.

The USAAF designation system only applied to aircraft ordered by the USAAF and did not apply to foreign aircraft acquired by Reverse Lend-Lease. For example, the Spitfires, Beaufighters, Ansons, etc. acquired from the Royal Air Force (RAF) kept their RAF designation and usually their serial number.

The USAAF/USAF aircraft designation consists of a minimum of three parts and a maximum of six parts. As an example, consider the Douglas TA-20K-15-DO Havoc, msn 23954, USAAF serial number 44-731. The six parts of the designation are indicated by the number in parenthesis shown below:

T	A	-20	K	-15	-DO
(1)	(2)	(3)	(4)	(5)	(6)

The definitions of the six parts of the designation are:

(1) Status or special-purpose prefix (Optional),

(2) Type symbol (Required),

(3) Model number (Required),

(4) Series letter (Optional; required for the 2d and later aircraft in the series),

(5) Block number (optional), and

(6) Manufacturer identification (required).

Each of these six items are described in detail below in a paragraph numbered 1 through 6 corresponding to the six items above.

1. Status or special-purpose prefix (Optional)

The status or special-purpose prefix indicates the aircraft’s development, status and/or secondary purpose. The first use of this code was the letter "X" indicating an experimental aircraft, usually a prototype. The code was also used for production aircraft that were modified for tests and the aircraft normally retained the X-prefix during the tests. For example, Boeing P-12E, s/n 31-553, was converted to an XP-12E for development tests; when re-engined with an SR-1340E engine, it became YP-12K; when equipped with a supercharger, it became XP-12L; and finally, the aircraft was converted back to a "stock" P-12E.

The second code introduced was "Y" for service test. If tests indicated that the "X" model had promise, the USAAS/USAAC/USAAF would order between 2 and 13 service test aircraft. Many of these were assigned to active duty squadrons who used them to determine their strengths and weaknesses. For example, the USAAC ordered 13 Y1B-17’s; the "1" in Y1B indicated procurement from F-1 Funds rather than regular appropriations. Many of these aircraft were assigned to the 2d Bombardment Group at Langley Field, Virginia for testing. The last pre-World War II code was "Z" indicating obsolete.

The codes used during the period 1939-45 are listed below along with an example of an aircraft using the prefix. This table indicates that the TA-20K-15-DO was an A-20K-15-DO that had been modified as a trainer.

Transport (1943 to date)

(North American CB-25J Mitchell)

Photographic (1945-47)

(North American FP-51D Mustang)

Ferret (1944-47)

(?)

Restricted (1942-47)

(Lockheed RP-38E Lightning) (see note below)

Trainer (1943 to date)

(Curtiss TP-40N)

Utility (1941 to date)

(Cessna UC-78 Bobcat) (see note below)

Staff transport (1945 to date)

(Boeing VB-17G Flying Fortress)

Experimental (1924 to date)

(Boeing XB-29 Superfortress)

Service test (1928 to date)

(Boeing YB-29 Superfortress)

Obsolete (1928-62)

(?)

NOTE: The prefix ”R” indicated that the aircraft was not to be used on combat missions. The codes UC for utility transport or cargo aircraft indicated that the aircraft could accommodate up to eight persons, including pilot, or a cargo weighing no more than 1,400 pounds (635 kg).

2. Type symbol (Required)

The type symbol identifies the basic purpose of the aircraft. For example, our TA-20K-15-DO was basically an attack aircraft ("A") that had been modified into a trainer ("T"). The following letter(s) were assigned during the period 1939-45; examples of an aircraft of each type is indicated.

Attack (1926-47; to B in ’48)

(Douglas A-26 Invader; to B-26 in ’48)

Powered target (1940-41)

(Bell A-7 Airacobra)

AG:

Assault glider (1942-44)

(Timm AG-2)

AT:

Advanced trainer (1925-47; to T in ’48)

(North American AT-6 Texan; to T-6 in ’48)

Bomber (1925 to date)

(Martin B-26 Marauder)

BC:

Basic combat (1936-40)

(North American BC-1)

BG:

Bomb glider (1942-44)

(Fletcher BG-1)

BQ:

Bomb, guided (1942-45)

(Boeing BQ-7 Flying Fortress)

BT:

Basic trainer (1930-47; to T in ’48)

(Vultee BT-13 Valiant; to T-13 In ’48)

Transport (1925 to date)

(Curtiss C-46 Commando)

CG:

Transport glider (1941-47; to G in ’48)

(Waco CG-4 Hadrian; to G-4 In ’48)

CQ:

Target Control (1942-47; became D-prefix in ’48)

(Beechcraft CQ-3 Expeditor; to DC-45 in ’48)

Photographic (1930-47; to R-prefix in ’48)

(Boeing F-9 Flying Fortress; to FB-17 in ’45 and RB-17 to ’48)

FG:

Fuel-carrying glider (1944-47)

(Cornelius FG-1)

FM:

Fighter, multiplace (1936-41)

(Bell FM-1 Airacuda)

Gyroplane (1935-39; to O and R in ’39)

(Kellett G-1; to R-2 in ’41)

GB:

Glide bomb (1942-47)

GT:

Glide torpedo (1942-47)

JB:

Jet-propelled bomb (1943-47)

Liason (1942-62; to O in ’62)

(Piper L-4 Cub)

Observation (1924-42; to L in ’42)

(Piper O-59 Cub; to L-4 in ’42)

OA:

Observation, amphibian (1925-47; to A in ’48)

(Consolidated OA-10 Catalina; to A-10 in ‘48)

OQ:

Target, flying model (1942-47; to Q in ’48)

(Frankfort OQ-3; to Q-3 in ’48)

Pursuit (1925-47; to F in ’48)

(Republic P-47 Thunderbolt; to F-47 in ’48)

PB:

Pursuit, biplace (1935-41)

(Consolidated PB-2)

PG:

Powered glider (1943-47; to G in ’48)

(Waco PG-3; to G-3 in ’48)

PQ:

Aerial target, manned (1942-47; to Q in ’48)

(Culver PQ-14; to Q-14 in ’48)

PT:

Primary trainer (1925-47; to T in ’48)

(Fairchild PT-14 Cornell; to T-14 in ’48)

Rotary wing (1941-47; to H in ’48)

(Sikorsky R-5 Dragonfly; to H-5 in ’48)

TG:

Trainer glider (1941-47)

(Taylorcraft TG-6)

3. Model number (Required)

The model number indicates the number of different models that had been ordered under each type designation, regardless of manufacturer. For example, the B-17 was the 17th bomber design; the P-40 the 40th fighter design; our TA-20K-15-DO was the 20th attack aircraft; etc.

4. Series letter (Optional; required for the 2d and later aircraft in the series)

The series letter was applied to the model number to indicate modifications of the original model. As a general rule, the letters "I" and "O" were not used as series letters. Normally, the first production aircraft did not have a series letter and the second aircraft in the series was given an "A" suffix, e.g., the first production Mustang was the P-51, the second was the P-51A, etc. Today, the first aircraft in the series is assigned the "A" suffix, the second "B", etc.

There were four reasons for changing the series letter, i.e.

1. When a change was made in the engine or engine series,

2. A new propeller of different make or size is fitted,

3. A major change in primary armament is made, and/or

4. A major change is made in structure or equipment installation that affects a model’s interchangeability or flying characteristics.

The modification of the aircraft configuration was not necessarily enough to cause a change in the letter, e.g., P-47D’s were produced in both razorback and bubble canopy versions.

In our example, the TA-20K-15-DO, the series was

A-20:

first production aircraft

A-20A:

second production aircraft

A-20B:

third production aircraft

A-20C:

fourth production aircraft

A-20D:

projected version with different engines; never built

A-20E:

17 converted A-20A’s with different engines

A-20F:

1 A-20A modified with new armament and turrets

A-20G:

fifth production aircraft with solid nose

A-20H:

sixth production aircraft

A-20J:

seventh production aircraft

A-20K:

eighth production aircraft

Therefore, the A-20K was the eighth production aircraft.

5. Block number (optional)

By 1941, the increasing complexity of aircraft made it desirable to identify minor differences between aircraft without changing the series letter. Since these changes were normally made on a number of consecutive aircraft in a particular production block, the term Block Number was used to identify the differences. The Block Number denotes a group of aircraft incorporating the same modifications, the parts of which are interchangeable for maintenance and servicing.

The first block of aircraft are identified by the numeric "-1" as in P-40F-1-CU. Initially, the second block of aircraft were to be identified by "-2" but it was realized that this would preclude identifying field modifications so the second block was identified as "-5" and then by fives, i.e., "-10", "-15", etc. Intermediate numbers were reserved for modifications made in service or at modification centers. The highest block numbers were assigned to Consolidated B-24J-210-CO Liberators.

In our example, the TA-20K-15-DO was one of the 275 Block 15 aircraft built.

6. Manufacturer identification (required)

The large aircraft programs of World War II saw the same basic type of aircraft being built by different companies and/or at different locations. For example, Boeing B-17 Flying Fortress’ were built by Boeing at Seattle, Washington, by Douglas at Long Beach, California and by Lockheed (Vega) at Burbank, California. The North American P-51 Mustang was built at North American’s plants in Inglewood, California and Dallas, Texas. In order to identify who built the aircraft at which plant, a two-alpha character manufactures identification code was created in 1941 and assigned to most aircraft. The only exception to this rule was when "one of a kind" aircraft were procured, e.g., the students of Notre Dame University designed and built one Model ND-1 single-seat sailplane that was "drafted" (conscripted) in Fiscal Year 1942 and assigned the designation TG-21. Since this was one of a kind, a code indicating Notre Dame U was not created and the glider was known simply as the TG-21.

The codes that were assigned during World War II are listed below. In our example, the TA-20K-15-DO, the ”DO” indicates that the aircraft was built by Douglas Aircraft Co. at their Santa Monica, California plant. The manufacturer’s codes and the aircraft produced or ordered at these locations are up through Fiscal Year 1945 are:

AE:

Aeronca Aircraft Corp., Middletown, Ohio (L-3, O-58, PT-19, PT-23, TG-5)

AG:

Air Glider, Inc., Akron, Ohio (TG-3)

BA:

Bell Aircraft Corp., Atlanta, Georgia (B-29)

BB:

Babcock Aircraft, Deland, Florida (CG-4)

BE:

Bell Aircraft Corp., Buffalo, New York (P-39, P-59, P-63, P-77, P-83)

BH:

Beech Aircraft Corp., Wichita, Kansas (A-38, AT-7, AT-10, AT-11, C-43, C-45, CQ-3, F-2)

BL:

Bellanca Aircraft, New Castle, Delaware (L-11)

BN:

Boeing Airplane Co., Renton, Washington (B-29, B-44, F-13)

BO:

Boeing Airplane Co., Seattle, Washington (A-20, B-17, B-29, B-38, B-39, B-40, BQ-7, C-73, C-75, C-97, C-98, C-105, C-108, F-9)

BR:

Briegleb Sailplane, Beverley Hills, California (TG-9, TG-13)

BS:

Bowlus Sailplane, San Francisco, California (CG-7, CG-8, TG-12)

BU:

Budd Manufacturing, Philadelphia, Pennsylvania (C-93)

BW:

Stearman Aircraft Division, Boeing Airplane Co., Wichita, Kansas (AT-15, B-29, BT-17, F-13, PT-13, PT-17, PT-18, PT-27)

CA:

Chase Aircraft Co., Inc., West Trenton, New Jersey (CG-14)

CE:

Cessna Aircraft Co., Wichita, Kansas (AT-8, AT-17, C-77, C-78, C-94, C-106, CG-4)

CF:

Consolidated-Vultee Aircraft Corp., Ft. Worth, Texas (AT-22, B-24, B-32, B-36, C-87, F-7)

CH:

Christopher Aircraft, St. Louis, Missouri (AG-1)

CK:

Curtiss-Wright Corp., Louisville, Kentucky (C-46, C-76)

CL:

Culver Aircraft, Wichita, Kansas (PQ-8, PQ-14)

CM:

Commonwealth Aircraft, Kansas City, Missouri (CG-3, CG-4)

CO:

Consolidated-Vultee Aircraft Corp., San Diego, California (B-24, B-32, B-41, B-46, BQ-8, C-99, F-7, OA-10, P-81)

CR:

Cornelius Aircraft, Dayton, Ohio (BG-3, FG-1)

CS:

Curtiss-Wright Corp., St. Louis, Missouri (A-25, A-40, AT-9, C-46, C-55, C-76, C-113)

CU:

Curtiss-Wright Corp., Buffalo, New York (C-46, P-36, P-40, P-46, P-47, P-53, P-55, P-60, P-62)

DC:

Douglas Aircraft Co., Chicago, Illinois (C-54)

DE:

Douglas Aircraft Co., El Segundo, California (A-20, A-24, A-26, A-33)

DH:

deHavilland Aircraft, Toronto, Ontario, Canada (F-8, PT-24)

DK:

Douglas Aircraft Co., Oklahoma City, Oklahoma (C-47, C-117)

DL:

Douglas Aircraft Co., Long Beach, California (A-20, A-26, B-17, C-47, C-74, C-110, CG-17, F-9)

DO:

Douglas Aircraft Co., Santa Monica, California (A-20, A-42, B-18, B-23, B-42, B-43, C-48, C-49, C-50, C-51, C-52, C-53, C-54, C-58, C-67, C-68, C-84, C-110, C-112, C-114, C-115, C-116, F-3, P-70)

DT:

Douglas Aircraft Co., Tulsa, Oklahoma (A-24, A-26, B-24, C-109)

FA:

The Fairchild Engine & Airplane Co., Hagerstown, Maryland (AT-13, AT-14, AT-21, BQ-3, C-61, C-82, C-86, C-88, C-96, PT-19, PT-23, PT-26)

FB:

The Fairchild Engine & Airplane Co., Burlington, North Carolina (AT-21)

FE:

Fleet Aviation Ltd., Fort Erie, Ontario, Canada (PT-23, PT-26)

FL:

Fleetwings, Inc., Bristol, Pennsylvania (A-39, BQ-1, BQ-2, BT-12, PQ-12)

FO:

Ford Motor Co., Willow Run, Michigan (B-24, C-109, CG-4, CG-13, PG-2)

FR:

Frankfort Sailplane, Joliet, Illinois (CG-1, CG-2, OQ-2, OQ-3, OQ-14, TG-1)

FT:

Fletcher Aircraft Corp., Pasadena, California (BG-1, BG-2, CQ-1)

GA:

G&A Aircraft Co, Willow Grove, Pennsylvania (CG-4, CG-16)

GC:

General Motors (Fisher), Cleveland, Ohio (P-74)

GE:

General Aircraft, Astoria, New York (CG-4)

GM:

General Motors (Fisher), Detroit, Michigan (P-74)

GN:

Gibson Refrigerator, Greenville, Michigan (CG-4)

GR:

Grumman Aircraft Corp., Bethpage, Long Island, New York (OA-9, OA-12, OA-13, OA-14)

HI:

Higgins Aircraft, Inc., New Orleans, Louisiana (C-46)

HO:

Howard Aircraft Corp., Chicago, Illinois (C-70, PT-23)

HU:

Hughes Aircraft Co., Culver City and San Diego, California (A-37, F-11)

IN:

Interstate Aircraft and Engineering, El Segundo, California (BQ-4, BQ-5, BQ-6, L-6, L-8, O-63)

KE:

Kellet Autogyro Corp., Philadelphia, Pennsylvania (O-60, R-2, R-3, R-8, R-10)

LK:

Laister-Kauffman Aircraft Co., St. Louis, Missouri (CG-4, CG-10, TG-4, TG-20)

LO:

Lockheed Aircraft Corp., Burbank, California (A-28, A-29, AT-18, B-34, B-37, C-36, C-40, C-56, C-57, C-59, C-60, C-63, C-66, C-69, C-85, C-101, C-111, F-4, F-5, F-14, O-56, P-38, P-49, P-58, P-80)

MA:

The Glenn L. Martin Co., Baltimore, Maryland (A-30, AT-23, B-26, B-27, B-48)

MC:

McDonnell Aircraft Co., St. Louis, Missouri (P-67)

MO:

The Glenn L. Martin Co., Omaha, Nebraska (AT-23, B-26, B-29, B-33)

NA:

North American Aviation, Inc., Inglewood, California (A-27, A-36, AT-6, AT-24, B-25, B-28, B-45, BT-14, F-6, P-51, P-64, P-82)

NC:

North American Aviation, Inc., Kansas City, Kansas (B-25)

ND:

Noorduyn Aviation Co., Ltd., Montreal, Quebec (AT-16, C-64)

NK:

Nash-Kelvinator Corp., Detroit, Michigan (F-10, R-6)

NO:

Northrop Aircraft, Inc., Hawthorne, California (A-31, B-35, B-49, C-100, F-15, P-56, P-61, P-79)

NT:

North American Aviation, Inc., Dallas, Texas (AT-6, B-24, C-82, F-6, P-51)

NW:

Northwestern Aeronautical Corp., St. Paul, Minnesota (CG-4, CG-13, PG-1, PG-2)

PI:

Piper Aircraft Corp., Lockhaven, Pennsylvania (C-83, L-4, L-14, O-59, TG-8)

PL:

Platt-LePage Aircraft Co., Eddystone, Pennsylvania (R-1)

PR:

Pratt, Read & Co., Eddystone, Pennsylvania (CG-4, TG-32)

RA:

Republic Aviation, Evansville, Indiana (P-47)

RD:

Read-York, Inc., Kenosha, Wisconsin (CG-12)

RE:

Republic Aviation, Farmingdale, Long Island, New York (AT-12, F-12, P-43, P-47, P-72)

RI:

Ridgefield Manufacturing Co., Ridgeville, New Jersey (CG-4, PG-2)

RO:

Robertson Aircraft, St. Louis, Missouri (CG-4)

RP:

The Radioplane Co., Van Nuys, California (OQ-2, OQ-3, OQ-14)

RY:

Ryan Aeronautical Co., San Diego, California (L-10, PT-20, PT-21, PT-22, PT-25)

SI:

Sikorsky Aircraft Division of United Aircraft Corp., Stratford, Connecticut (OA-11, R-4, R-5, R-6, R-7)

SL:

St. Louis Aircraft, St. Louis, Missouri (CG-5, CG-6, PT-19, PT-23)

SP:

Spartan Aircraft, Tulsa, Oklahoma (C-71)

SW:

Schweizer Aircraft, Elmira, New York (TG-2, TG-3)

TA:

Taylorcraft Aviation, Alliance, Ohio (C-95, L-2, O-57, TG-6, TG-33)

TI:

Timm Aircraft, Van Nuys, California (AG-2, CG-4)

UN:

Universal Molded Products, Bristol, Virginia (L-7)

VE:

Lockheed (Vega) Aircraft Corp., Burbank, California (B-17, B-40, F-9)

VI:

Canadian Vickers, Ltd., Montreal, Quebec, Canada (OA-10)

VN:

Vultee Aircraft Corp., Nashville, Tennessee (A-31, A-35, BT-13, P-38)

VU:

Vultee Aircraft Corp., Downey, California (BT-15, P-54, P-66)

VW:

Stinson Aircraft Division of Consolidated Vultee Corp., Wayne, Michigan (AT-19, C-81, C-91, CQ-2, L-1, L-5, L-9, L-12, L-13, O-49, O-62)

WA:

Ward Furniture Co., Fort Smith Arkansas (CG-4)

WO:

Waco Aircraft Co., Troy, Ohio (C-62, C-72, CG-3, CG-4, CG-13, CG-15, PG-3)